Heat olive oil on medium-high in a large pan.
Add all spices to a small bowl and stir to combine.
In a large bowl, add the large chunks of pork and coat all sides of the pork with the spice mixture. You want all sides and pieces to be covered well.
Once the pork is seasoned and pan is hot, add the pork to the pan (working in batches if needed) to make sure you don’t overcrowd the pan. Sear pork on all sides until a brown crust starts to form (but before it burns).
Transfer the seared pork to the slow cooker and pour the orange juice over the pork.
Cover and cook on low for 8 hours or on high for 4 hours, until the pork is tender and easily pulls apart with a fork.
When the pork is tender, use two forks or tongs to shred the pork into bite sized pieces while still in the liquid. Do not discard the liquid yet.
Preheat the oven to 425°F.
Transfer the pork to a baking sheet, spreading evenly with minimal overlap. Take ½ cup to 1 cup of the juices from the crockpot and drizzle over the pork to add more flavor and does not dry out while crisping.
Bake at 425°F for 15 to 20 minutes, or until the tops are starting to look a little crispy.
Assemble the tacos with your favorite toppings and serve!